What happens when a follower of Jesus Christ leads a city where millions of Muslims live? A Christian man with Chinese ancestry is finding out that this is not an easy task as he seeks to extend his term as governor of the Indonesian capital, Jakarta.

Basuki Tjahaja Purnama, or "Ahok" as he is widely known in Indonesia, earlier declared his plan to seek a new mandate in Jakarta's special elections next year.

Although he has good plans and intentions for the city, Ahok faces a rough road ahead to remaining as Jakarta's governor, with some of his Muslim constituents saying they won't cast their vote for him because he is a Christian.

Muslim leaders are using mosques during prayer time to warn Indonesians against voting for Ahok, the second Christian governor of Jakarta.

Cleric Alwi Wahid warned fellow Muslims against voting for a non-believer, saying it is a form of disloyalty to Islam, according to the Australian news agency ABC.

"Be careful on the judgment day — God will ask you, why did you choose the infidel as the leader, while I have warned you not to. Believers should not choose a non-Muslim as their leader," the Muslim faith leader reportedly said during a sermon at the Al Furqon mosque in central Jakarta.

Ahok is up against two Muslim opponents in the coming elections — former education minister Anies Baswedan and surprise late entry Agus Harimurti Yudhoyono, a one-time army major and the son of the former president Susilo Bambang Yudhoyono.

Mohammad Siddik from the Indonesian Supreme Council for Islamic Propagation meanwhile warned that electing a non-Muslim as Jakarta governor can lead to instability. He has openly campaigned against Ahok.

"We are calling the people, Muslims call the people not to vote for Ahok because we are also guided by our faith, by the Quran," he said.

Despite the efforts to put him down, the Christian politician is unfazed, believing that his fellow Indonesians know better.

"We will learn. [Although] we are just 71 years independent, I think we are more advanced if you compare [us] to the United States of America," Ahok told ABC.